1. Field
A hold type display device and a driving method thereof are provided.
2. Related Art
In hold type display devices like a liquid crystal display (LCD) or organic light emitting diode (OLED), a motion blurring phenomenon is displayed on a screen. During this motion blurring phenomenon a screen is not clear but blurred in a motion picture by a maintenance characteristic. This maintenance characteristic will be explained in conjunction with FIGS. 1 to 4, which represent a data characteristic of a liquid crystal display device and a cathode ray tube (CRT).
The CRT, as shown in FIG. 1, is an impulse type display device that displays data by making a phosphorus emit light for a very short time in an early stage of one frame period and where most of the one frame period remains as a pause interval. Accordingly, in the CRT, a perceived image is displayed clearly, as shown in FIG. 2. The perceived image is of an image that an observer perceives.
In a liquid crystal display device, as shown in FIG. 3, data is supplied to a liquid crystal for a scanning period when a scan high voltage is supplied and the data supplied to the liquid crystal is maintained in a non-scanning period that takes most of one frame period. Accordingly, the display picture is blurred in the liquid crystal display device, as shown in FIG. 4, because of a motion blurring phenomenon. The perceived image results from an integration effect of the image which temporarily lasts in an eye that follows a movement. Accordingly, even though the response speed of the liquid crystal display device is fast, an observer sees a blurred screen because of discordance between the movement of the eye and the static image of each frame.
Conventionally, in order to decrease the motion blurring of the liquid crystal display device of the related art, the holding time is reduced and black data is inserted for a frame period.
The black data insertion (BDI) method reduces the holding time D1-D5 of frame data within each frame and inserts black data B1-B5, as in FIG. 6. This method is different from a normal method that inserts one frame data for each frame, as in FIG. 5. Thus, a liquid crystal display device is driven by a pseudo-impulse type to decrease the motion blurring phenomenon.
Because the holding time of each frame is reduced and the black data are inserted in the black data insertion method like this the brightness is remarkably decreased in the black data insertion method, as in FIG. 7.